A pneumatic actuator ball valve (often listed as a pneumatic actuated ball valve) is specified by seven decisions: the valve series and size, the end connection, double acting or spring return, the fail position, the solenoid valve and its coil voltage, the temperature, and the air supply. The two charts below cover our own valve range, and the checklist near the end turns those decisions into an RFQ (request for quotation) line that a supplier can quote without a week of follow-up questions.
We are YZNG TRONG, a stainless steel ball valve manufacturer in Taiwan since 1999. We build the pneumatic actuators, NAMUR solenoid valves, limit switch boxes and ISO 5211 mounting brackets ourselves, and our pneumatic ball valve assemblies leave the factory with the actuator mounted and tested. The figures on this page come from our own dimension sheets and product data.
Key points
- On our V-2AM two-piece and V-3AM three-piece valves, the ISO 5211 pad steps up with size: F03/F04 for 3/8″ to 3/4″, F04/F05 for 1″ to 1-1/4″, F05/F07 for 1-1/2″ to 2″, and F07/F10 for 2-1/2″ to 4″.
- Our quotation for an automated valve includes the actuator by default, so the RFQ does not need an actuator model. It needs the acting type, the air pressure at the valve and the service conditions.
- On the V-2AM and V-3AM, the valve body is rated −20 °C to +180 °C with PTFE (polytetrafluoroethylene) seats and the actuator −20 °C to +80 °C. The assembly is limited by whichever part reaches its limit first.
- Double acting or spring return is specified when you order and cannot be changed in the field. Put it on the RFQ, together with fail-closed or fail-open for spring return.
How the Actuator Is Matched to a Pneumatic Actuator Ball Valve
The actuator has to do two things: bolt onto the valve and turn it reliably. The first is settled by the ISO 5211 pad. The second depends on the valve’s break torque and on the air pressure the actuator receives, and when one supplier makes and assembles both halves, matching them is that supplier’s job.
Break torque is the twisting force needed to start the ball moving from rest. It is usually the highest torque the actuator meets in the stroke, because the ball has been pressed against its seats while it sat still. A pneumatic actuator’s output, in turn, rises and falls with its supply pressure. When the valve and the actuator come from different suppliers, somebody has to put those two numbers side by side, and a mismatch can start at that hand-off. Our Guide de sélection des actionneurs de vannes explains what raises break torque in service.
For our assemblies, the RFQ does not have to name an actuator model. What we need is the acting type, the air pressure that reaches the valve, the media, the line pressure, the temperature and how often the valve will cycle. Break torque values for each V-2AM and V-3AM size are available on request if your own standard asks for them.
The mounting side is defined by ISO 5211, the international standard for attaching part-turn actuators to industrial valves. It sets the flange dimensions and the dimensions of the drive that couples the actuator to the valve stem. On a valve, this mounting face is called the pad, and its size is given as an F code such as F03, F05, F07 or F10. A higher number is a larger pad for a larger actuator.
Chart 1: Which of Our Ball Valves Take a Pneumatic Actuator
The six series below are built with an ISO 5211 pad for direct actuator mounting and cover threaded, flanged and sanitary lines from 1/4″ to 4″. Pick the series by body type, size and end connection first; the pad follows from that choice, and the actuator is matched to the valve in our quotation.
| Series | Corps | Tailles | Port | Fixation de l'actionneur | Raccords d'extrémité |
|---|---|---|---|---|---|
| 1PC-PN | D'un seul tenant | 3/8″ only | Reduced | ISO 5211 pad integral to the body, no bracket or coupling | PT, NPT or PF thread, made to order |
| V-2AM | En deux parties | 3/8″ to 4″ | Full | ISO 5211 direct mount, F03 to F10 by size | Female PT thread; NPT and PF made to order |
| V-3AM | En trois pièces | 3/8″ to 4″ | Full | ISO 5211 direct mount, F03 to F10 by size | PT, NPT or PF thread; socket weld; butt weld |
| MV-3DM | à 3 voies, à raccord en L ou à raccord en T | 1/4″ to 2″ | — | Dual ISO 5211 pad, direct mount | PT, NPT or PF thread |
| F-2BM, F-2DM, F-2KM, F-2EM | Two-piece flanged | 1/2″ to 4″ | Full | ISO 5211 direct mount | ASME Class 150 or 300; JIS 10K or 20K |
| V-3NM, V-3NM-L3 | Ensemble sanitaire en trois pièces | 1/2″ to 4″ | Full | ISO 5211 high-platform pad, F03 to F10 by size | Tri-Clamp or extended butt weld |
PT is a taper pipe thread (Rc), PF is a parallel pipe thread (G), and NPT is the American taper pipe thread. Pneumatic versions for vacuum lines, 3-way vacuum service, sanitary 3-way diverting et extrémités à soudure bout à bout prolongées also carry an ISO 5211 pad and have their own product pages.
Manual valves without a pad, such as our V-3A three-piece and R-1B one-piece valves, are not built for direct actuator mounting. For automation, choose the 1PC-PN (3/8″ only), V-2AM or V-3AM in place of the R-1B. If a line may be automated later, say so at order stage and we can supply the V-3AM in place of the V-3A.
Chart 2: ISO 5211 Pad, Bore and Length by Size (V-2AM and V-3AM)
The V-2AM and V-3AM carry the same ISO 5211 pad size for size, and both are full port, so the bore is close to the nominal pipe size. The difference that matters on site is length: at every size, the three-piece PT version is longer than the two-piece. All figures are taken from the dimension sheets on each product page.
| Valve size | DN (metric nominal size) | Bore, V-2AM (mm) | Bore, V-3AM (mm) | Length L, V-2AM (mm) | Length L, V-3AM PT (mm) | ISO 5211 pad |
|---|---|---|---|---|---|---|
| 3/8″ | DN10 | 12.5 | 12.5 | 58.0 | 65.5 | F03/F04 |
| 1/2″ | DN15 | 15.0 | 15.0 | 60.0 | 65.5 | F03/F04 |
| 3/4″ | DN20 | 20.0 | 20.0 | 70.0 | 77.6 | F03/F04 |
| 1″ | DN25 | 25.0 | 25.0 | 82.0 | 83.5 | F04/F05 |
| 1-1/4″ | DN32 | 32.0 | 32.0 | 96.0 | 102.5 | F04/F05 |
| 1-1/2″ | DN40 | 38.0 | 40.0 | 112.0 | 117.6 | F05/F07 |
| 2″ | DN50 | 50.0 | 50.0 | 126.0 | 130.2 | F05/F07 |
| 2-1/2″ | DN65 | 65.0 | 65.0 | 155.0 | 158.6 | F07/F10 |
| 3″ | DN80 | 80.0 | 80.0 | 170.0 | 177.8 | F07/F10 |
| 4″ | DN100 | 100.0 | 100.0 | 216.5 | 225.2 | F07/F10 |
Read the chart in three ways. The pad column matters when the valve has to match actuators already used elsewhere in your plant, or when a drawing calls out the pad; every size on both sheets lists two pad codes because each pad is drilled for both flange sizes, so an actuator with either flange bolts on directly. At 3/8″ to 3/4″, for example, that means an F03 or an F04 actuator. The length columns matter when you swap one series for the other in an existing threaded line, because the V-3AM PT is 1.5 mm to 8.7 mm longer depending on size. Both series are full port, and the one difference in bore is at 1-1/2″, where the V-3AM is 40.0 mm and the V-2AM 38.0 mm.
Double Acting or Spring Return: Decide Before You Send the RFQ
Choose double acting when the process does not need the valve to go to a set position if the air supply is lost; a double acting actuator has no defined fail position. Choose spring return when the valve must move to a set position on air loss. On our actuators the acting type is specified when you order and cannot be changed in the field, so it belongs on the first line of the RFQ rather than in a later email.
For spring return, add the fail position: fail-closed (normally closed) or fail-open (normally open). Fail-closed suits a feed or dosing line that must stop when the air drops. Fail-open suits a cooling or vent line that must keep flowing. Settle it with the process engineer before the RFQ goes out.
Expect the spring return assembly to be the bigger of the two at the same valve size. A spring return actuator spends part of its air stroke compressing its springs, and on the return stroke the springs alone have to turn the ball, so it needs a larger body to give the same usable torque. Check the installed height if the valve has to fit inside a machine frame or under a guard. Our spring return vs double acting comparison covers the other trade-offs.
Solenoid Valve, Limit Switch Box and Positioner
The solenoid valve follows from the acting type: a double acting actuator needs a 5/2 way solenoid valve, and a spring return actuator needs a 3/2 way. After that, the only solenoid decision is coil voltage. The limit switch box and the positioner are optional, and only the positioner changes what the valve does.
- Solenoid valve. Notre Électrovanne NAMUR bolts straight onto the actuator with no tubing between them. NAMUR here means the standard air-port and bolt pattern on the actuator body that accepts the solenoid valve directly. It has a G1/4 air port, a working air pressure of 1 to 8 bar (about 15 to 116 psi), coils for 24 V DC, 110 V AC or 220 V AC, a manual override for commissioning, and an IP67 enclosure. IP67 is a rating under IEC 60529, the standard for enclosure protection (IP code): dust-tight, and able to survive temporary immersion in water.
- Limit switch box. We make one model, the LSB-01 limit switch box: two mechanical single-pole double-throw (SPDT) switches for open and closed feedback, an open/closed dome indicator on top, an IP67 enclosure, and NAMUR mounting on top of the actuator. With a single model, the RFQ only needs the words “with limit switch box”.
- Positioner. Needed only when the valve has to hold positions between open and closed for flow control, known as modulating service. For on/off duty, leave it off. The one-piece 1PC-PN is built for on/off duty only and is not a throttling valve.
Temperature and Air Supply: Two Limits Outside the Valve
Two limits sit outside the valve body: the actuator sets the temperature limit, and the air that reaches the actuator has to be 4 to 8 bar. Our V-2AM, V-3AM and MV-3DM bodies with PTFE seats are rated −20 °C to +180 °C (−4 °F to +356 °F), while our pneumatic actuators are rated −20 °C to +80 °C (−4 °F to +176 °F), so the assembly is limited by whichever part reaches its limit first. On the sanitary V-3NM, the fully encapsulated seat is rated −20 °C to +80 °C.
This catches buyers out because a spec sheet often shows the valve rating in large type and the actuator rating somewhere else. In the RFQ, give the process temperature and the ambient temperature around the valve, so both can be checked against the actuator. If the line runs close to the actuator’s rating, send the valve, the actuator and the process temperature with the RFQ. Our 304 stainless steel mounting kit (BL-304) can set the actuator back from a hot valve body, and its linkage is matched to each valve and actuator combination.
Our pneumatic actuators are specified for 4 to 8 bar supply air (about 58 to 116 psi). Quote the pressure that actually reaches the valve, not the compressor setting, because long branch lines and shared headers lose pressure on the way. Air quality matters as well: water and oil carried in the air end up in the solenoid valve and the actuator. If your plant specifies compressed air by purity class under ISO 8573-1, which grades air by particles, water and oil, put the class in the RFQ.
What Our Quotation Includes and How It Ships
Our quotation for a pneumatic actuator ball valve covers the valve and the actuator, assembled. The solenoid valve, limit switch box and positioner are options you add. The assembly is mounted in our factory and tested before it ships, so it arrives as one unit rather than a box of parts to fit on site.
- Testing. Each assembly is stroke tested and torque tested before it ships, and our ball valves are pressure tested to API 598, the American Petroleum Institute standard for valve inspection and testing.
- Documents. Material test reports (MTR), dimension drawings, break torque values and a copy of our ISO 9001 certificate are available on request.
If you are comparing suppliers rather than models, our guide to verifying a 3 piece ball valve manufacturer covers which documents to ask for, and our valve actuator manufacturer page explains what changes when one factory supplies both the valve and the actuator.
RFQ Checklist for a Pneumatic Actuator Ball Valve
Send these ten lines and a supplier can quote without coming back to you. The first six fix the hardware; the last four fix the conditions it has to meet.
- Valve series or body type: one-piece, two-piece, three-piece, 3-way L-port or T-port, flanged or sanitary.
- Size and quantity for each size.
- End connection: PT, NPT or PF thread, socket weld, butt weld, flange class or Tri-Clamp.
- Body material: 316 (cast grade CF8M) or 304 (cast grade CF8).
- Double acting or spring return, and for spring return, fail-closed or fail-open.
- Accessories: solenoid valve with coil voltage, limit switch box, and a positioner only for modulating service.
- Media, line pressure and process temperature.
- Ambient temperature at the valve, indoors or outdoors.
- Supply air pressure at the valve, and the air purity class if your plant uses one.
- Documents you need with the shipment, and branding if the actuator should carry your name.
A complete line looks like this: “V-2AM, 1″, PT female thread, CF8M, 20 pcs, spring return fail-closed, 3/2 NAMUR solenoid valve 24 V DC, limit switch box, water at 60 °C, 6 bar air at the valve, MTR required.”
Three Mistakes That Slow Down an Order
The three to watch are a solenoid valve that does not match the acting type, a positioner on on/off duty, and a missing coil voltage. Each is quick to settle at RFQ stage and slow to fix after the quote, and all three are easy to miss when an automated ball valve is specified for the first time.
- Choosing the solenoid valve before the acting type. A 5/2 way valve on a spring return actuator, or a 3/2 way on a double acting one, and the valve will not cycle. Decide double acting or spring return first, and the solenoid function follows.
- Adding a positioner to on/off duty. A positioner adds cost and setup for no benefit when the valve only opens and closes. Specify it only when the valve has to hold intermediate positions.
- Leaving out the coil voltage. The solenoid valve cannot be quoted without it, and 24 V DC versus 220 V AC is not a detail anyone should guess.
Our valve actuator manufacturer page lists more mismatches to check when you specify an automated valve, such as assuming any actuator bolts onto any valve.
Questions fréquemment posées
Can I buy your solenoid valve or limit switch box for an actuator I already have?
Yes. Our NAMUR solenoid valve bolts onto any actuator with a NAMUR interface, including actuators from other makers, and it is sold on its own as well as in a package. If you are not sure which solenoid function your actuator takes, send us the actuator model and we will tell you. The LSB-01 limit switch box fits any NAMUR-compatible pneumatic actuator. Tell us the actuator make and model with the order so we can confirm the fit.
Does a limit switch box confirm that the valve has sealed?
No. A limit switch box reports where the actuator shaft has stopped, open or closed. That tells the control system the valve has reached its end position, which is what most interlocks need. It cannot tell you whether the seats are holding pressure, because a worn seat or debris on the ball can leak while the shaft sits fully closed. Our LSB-01 uses two mechanical SPDT switches with a dome indicator on top. If your process needs proof of shutoff, add a pressure or flow check downstream of the valve.
Should the valve body be 304 or 316?
Choose 316, cast as CF8M, when chlorides are present in the media, the washdown water or the air around the valve, for example on coastal sites. The molybdenum in 316 resists the pitting that chlorides cause. 304, cast as CF8, suits clean water, compressed air and many oils where chlorides are not a concern. On our V-3AM three-piece valves, CF8M is the stock material and CF8 is made to order. If you are unsure, send the media name and concentration with the RFQ so the material can be checked against the actual service.
Can the actuator carry our company’s brand?
Yes. Our pneumatic actuators can be supplied under your brand, and private label options include laser marking, stamping, labels and printed boxes. This suits distributors and OEMs who sell the assembly as part of their own range. Put the branding requirement in the first RFQ, with artwork if you have it, because it affects how the order is marked and packed. Private label is available on the valve as well as the actuator, so the whole assembly can ship under one name.
Where can I find dimension drawings before I order?
The V-2AM and V-3AM product pages carry dimension sheets with bore, length and ISO 5211 pad for every size from 3/8″ to 4″. The V-3AM has separate sheets for PT thread, socket weld and butt weld ends. Their lengths match the PT version except at 3/8″, where the weld versions are 60.5 mm; the socket weld sheet adds the socket bore and the butt weld sheet adds the pipe OD. The sheets show the valve without the actuator. The MV-3DM, flanged and V-3NM product pages carry their own dimension sheets; for the 1PC-PN, ask us and we will send the dimensions.
Summary
To specify a pneumatic actuator ball valve, choose the series and size from Chart 1, read the pad and length from Chart 2, then decide double acting or spring return and the fail position. Add the solenoid valve and its coil voltage, check the temperature against the actuator rather than the valve, give the air pressure at the valve, and send the ten-line checklist with your RFQ. We make the valve, the actuator, the solenoid valve and the limit switch box, and ship them assembled and tested.